An electrical motor will commonly comprise a motor stator having at least two coil windings thereon, a motor protector which is connected in series with at least one of the windings, and a switch having terminals which are selectively connected to the motor protector and to the ends of the windings. A relatively simple form of motor such as a single phase induction motor will have two windings and a switch having at least three terminals. The motor protector will have two terminals. When the connections are made between the winding ends and the terminals of the protector and the switch, at least one of the winding ends is connected to one of the protector terminals and the remaining winding ends are connected to switch terminals. A direct connection is made between the remaining protector terminal and one of the switch terminals. Frequently, two of the winding ends will be connected commonly to the one protector terminal so that the remaining two winding ends are connected individually to switch terminals.
Other types of electrical motors having more complex terminals may have additional winding ends and may have in excess of three terminals on the switch.
It is common practice in the electrical motor art to make the required connections for an electric motor by means of lead wires extending between the ends of the windings and the terminals of the protector and the motor. The manufacturing process thus requires that after the coils have been wound on the stator core, the lead wires be connected to the ends of the coil windings by crimped connections and these connections must be insulated. Also, color-coded wires must be used when these lead wires are connected to the winding ends in order to indicate the precise terminals in the protector or switch to which the particular leads must be connected. The leads are provided with tab receptacles on their free ends so that after the switch and the protector are assembled to the stator, a technician can connect the lead wires to the terminals of the switch and protector in accordance with a wiring diagram that shows the color-coded wires extending to their proper terminals.
The manufacturing method described above is time consuming, requires considerable skilled manual labor, and presents many opportunities for errors or mistakes. For example, when the lead wires are connected by crimped connections to the ends of the coil windings, the technician performing this operation must select the proper colors of lead wires for predetermined winding ends. At the later stage when the lead wires are connected to the terminals, the technician again must select the proper lead wires and identify the proper terminal in the protector or the switch to which the lead must be connected. An additional disadvantage of this known manufacturing method is that several electrical interfaces are interposed between the ends of the coil windings and the terminals on the protector or switch; an electrical interface is formed at the crimped connection between the lead wire and the coil winding end, an additional interface exists at the crimped connection between the lead wire and the terminal on the end of the lead wire, and the final interface exists at the connection between the terminal tab on the switch and the receptacle on the lead wire. It is always desirable to cut down on the number of electrical interfaces in a wiring system in order to improve reliability and the wiring systems used for electric motors would be improved if the number of interfaces could be reduced.
The present invention is directed to an improved wiring system for electrical motors which makes use of an electrical connector arranged such that the number of interfaces is substantially reduced, the number of parts required (such as terminals and wires) is substantially reduced, and the possibility of mistakes being made in the wiring process is substantially eliminated.